Replace your Gloss Enhancer cart with the cheapest genuine HP C9459A on eBay. Expiration dates mean nothing for these inks. This may or may not be applicable to the Z1200: in my Z3200 there's a submenu option to turn off that ink channel, although your paper profile will bypass that and turn it on anyway if it's a glossy finish. Since I started only using matte finish I haven't run out of Gloss Enhancer, and I print several miles of 24" roll stock annually.